gdiplus: Add a fallback method for getting HDC's from Graphics objects.
Native does this in more cases (at least for all bitmap graphics
objects), but using gdi32 objects when we can should perform better.
diff --git a/dlls/gdiplus/graphics.c b/dlls/gdiplus/graphics.c
index 8850110..8e203f3 100644
--- a/dlls/gdiplus/graphics.c
+++ b/dlls/gdiplus/graphics.c
@@ -4663,6 +4663,9 @@
return ret;
}
+/* Color used to fill bitmaps so we can tell which parts have been drawn over by gdi32. */
+static const COLORREF DC_BACKGROUND_KEY = 0x0c0b0d;
+
GpStatus WINGDIPAPI GdipGetDC(GpGraphics *graphics, HDC *hdc)
{
TRACE("(%p, %p)\n", graphics, hdc);
@@ -4673,14 +4676,61 @@
if(graphics->busy)
return ObjectBusy;
- if (!graphics->hdc)
+ if (!graphics->hdc ||
+ (graphics->image && graphics->image->type == ImageTypeBitmap && ((GpBitmap*)graphics->image)->format & PixelFormatAlpha))
{
- WARN("no HDC for this graphics\n");
- *hdc = NULL;
- return GenericError;
+ /* Create a fake HDC and fill it with a constant color. */
+ HDC temp_hdc;
+ HBITMAP hbitmap;
+ GpStatus stat;
+ GpRectF bounds;
+ BITMAPINFOHEADER bmih;
+ int i;
+
+ stat = get_graphics_bounds(graphics, &bounds);
+ if (stat != Ok)
+ return stat;
+
+ graphics->temp_hbitmap_width = bounds.Width;
+ graphics->temp_hbitmap_height = bounds.Height;
+
+ bmih.biSize = sizeof(bmih);
+ bmih.biWidth = graphics->temp_hbitmap_width;
+ bmih.biHeight = -graphics->temp_hbitmap_height;
+ bmih.biPlanes = 1;
+ bmih.biBitCount = 32;
+ bmih.biCompression = BI_RGB;
+ bmih.biSizeImage = 0;
+ bmih.biXPelsPerMeter = 0;
+ bmih.biYPelsPerMeter = 0;
+ bmih.biClrUsed = 0;
+ bmih.biClrImportant = 0;
+
+ hbitmap = CreateDIBSection(NULL, (BITMAPINFO*)&bmih, DIB_RGB_COLORS,
+ (void**)&graphics->temp_bits, NULL, 0);
+ if (!hbitmap)
+ return GenericError;
+
+ temp_hdc = CreateCompatibleDC(0);
+ if (!temp_hdc)
+ {
+ DeleteObject(hbitmap);
+ return GenericError;
+ }
+
+ for (i=0; i<(graphics->temp_hbitmap_width * graphics->temp_hbitmap_height); i++)
+ ((DWORD*)graphics->temp_bits)[i] = DC_BACKGROUND_KEY;
+
+ SelectObject(temp_hdc, hbitmap);
+
+ graphics->temp_hbitmap = hbitmap;
+ *hdc = graphics->temp_hdc = temp_hdc;
+ }
+ else
+ {
+ *hdc = graphics->hdc;
}
- *hdc = graphics->hdc;
graphics->busy = TRUE;
return Ok;
@@ -4690,12 +4740,40 @@
{
TRACE("(%p, %p)\n", graphics, hdc);
- if(!graphics)
+ if(!graphics || !hdc)
return InvalidParameter;
- if(graphics->hdc != hdc || !(graphics->busy))
+ if((graphics->hdc != hdc && graphics->temp_hdc != hdc) || !(graphics->busy))
return InvalidParameter;
+ if (graphics->temp_hdc == hdc)
+ {
+ DWORD* pos;
+ int i;
+
+ /* Find the pixels that have changed, and mark them as opaque. */
+ pos = (DWORD*)graphics->temp_bits;
+ for (i=0; i<(graphics->temp_hbitmap_width * graphics->temp_hbitmap_height); i++)
+ {
+ if (*pos != DC_BACKGROUND_KEY)
+ {
+ *pos |= 0xff000000;
+ }
+ pos++;
+ }
+
+ /* Write the changed pixels to the real target. */
+ alpha_blend_pixels(graphics, 0, 0, graphics->temp_bits,
+ graphics->temp_hbitmap_width, graphics->temp_hbitmap_height,
+ graphics->temp_hbitmap_width * 4);
+
+ /* Clean up. */
+ DeleteDC(graphics->temp_hdc);
+ DeleteObject(graphics->temp_hbitmap);
+ graphics->temp_hdc = NULL;
+ graphics->temp_hbitmap = NULL;
+ }
+
graphics->busy = FALSE;
return Ok;
